Driver core: add device_type to struct device

This allows us to add type specific attributes, uevent vars and
release funtions.

A subsystem can carry different types of devices like the "block"
subsys has disks and partitions. Both types create a different set
of attributes, but belong to the same subsystem.

This corresponds to the low level objects:
  kobject   -> device       (object/device data)
  kobj_type -> device_type  (type of object/device we are embedded in)
  kset      -> class/bus    (list of objects/devices of a subsystem)

Signed-off-by: Kay Sievers <kay.sievers@novell.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 49 insertions, 20 deletions

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 7a5336f7df89..34ac18778d8a 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -95,6 +95,8 @@ static void device_release(struct kobject * kobj)
 
         if (dev->release)
                 dev->release(dev);
+        else if (dev->type && dev->type->release)
+                dev->type->release(dev);
         else if (dev->class && dev->class->dev_release)
                 dev->class->dev_release(dev);
         else {
@@ -206,19 +208,25 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj, char **envp,
         if (dev->bus && dev->bus->uevent) {
                 /* have the bus specific function add its stuff */
                 retval = dev->bus->uevent(dev, envp, num_envp, buffer, buffer_size);
-                        if (retval) {
-                        pr_debug ("%s - uevent() returned %d\n",
+                if (retval)
+                        pr_debug ("%s: bus uevent() returned %d\n",
                                   __FUNCTION__, retval);
-                }
         }
 
         if (dev->class && dev->class->dev_uevent) {
                 /* have the class specific function add its stuff */
                 retval = dev->class->dev_uevent(dev, envp, num_envp, buffer, buffer_size);
-                        if (retval) {
-                                pr_debug("%s - dev_uevent() returned %d\n",
-                                         __FUNCTION__, retval);
-                }
+                if (retval)
+                        pr_debug("%s: class uevent() returned %d\n",
+                                 __FUNCTION__, retval);
+        }
+
+        if (dev->type && dev->type->uevent) {
+                /* have the device type specific fuction add its stuff */
+                retval = dev->type->uevent(dev, envp, num_envp, buffer, buffer_size);
+                if (retval)
+                        pr_debug("%s: dev_type uevent() returned %d\n",
+                                 __FUNCTION__, retval);
         }
 
         return retval;
@@ -269,37 +277,50 @@ static void device_remove_groups(struct device *dev)
 static int device_add_attrs(struct device *dev)
 {
         struct class *class = dev->class;
+        struct device_type *type = dev->type;
         int error = 0;
         int i;
 
-        if (!class)
-                return 0;
-
-        if (class->dev_attrs) {
+        if (class && class->dev_attrs) {
                 for (i = 0; attr_name(class->dev_attrs[i]); i++) {
                         error = device_create_file(dev, &class->dev_attrs[i]);
                         if (error)
                                 break;
                 }
+                if (error)
+                        while (--i >= 0)
+                                device_remove_file(dev, &class->dev_attrs[i]);
         }
-        if (error)
-                while (--i >= 0)
-                        device_remove_file(dev, &class->dev_attrs[i]);
+
+        if (type && type->attrs) {
+                for (i = 0; attr_name(type->attrs[i]); i++) {
+                        error = device_create_file(dev, &type->attrs[i]);
+                        if (error)
+                                break;
+                }
+                if (error)
+                        while (--i >= 0)
+                                device_remove_file(dev, &type->attrs[i]);
+        }
+
         return error;
 }
 
 static void device_remove_attrs(struct device *dev)
 {
         struct class *class = dev->class;
+        struct device_type *type = dev->type;
         int i;
 
-        if (!class)
-                return;
-
-        if (class->dev_attrs) {
+        if (class && class->dev_attrs) {
                 for (i = 0; attr_name(class->dev_attrs[i]); i++)
                         device_remove_file(dev, &class->dev_attrs[i]);
         }
+
+        if (type && type->attrs) {
+                for (i = 0; attr_name(type->attrs[i]); i++)
+                        device_remove_file(dev, &type->attrs[i]);
+        }
 }
 
 
diff --git a/drivers/usb/input/hid-lgff.c b/drivers/usb/input/hid-lgff.c
index e47466268565..4f4fc3be192e 100644
--- a/drivers/usb/input/hid-lgff.c
+++ b/drivers/usb/input/hid-lgff.c
@@ -32,7 +32,7 @@
 #include <linux/hid.h>
 #include "usbhid.h"
 
-struct device_type {
+struct dev_type {
         u16 idVendor;
         u16 idProduct;
         const signed short *ff;
@@ -48,7 +48,7 @@ static const signed short ff_joystick[] = {
         -1
 };
 
-static const struct device_type devices[] = {
+static const struct dev_type devices[] = {
         { 0x046d, 0xc211, ff_rumble },
         { 0x046d, 0xc219, ff_rumble },
         { 0x046d, 0xc283, ff_joystick },
diff --git a/include/linux/device.h b/include/linux/device.h
index da7221913114..e1e164f81eea 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -328,6 +328,13 @@ extern struct class_device *class_device_create(struct class *cls,
                                         __attribute__((format(printf,5,6)));
 extern void class_device_destroy(struct class *cls, dev_t devt);
 
+struct device_type {
+        struct device_attribute *attrs;
+        int (*uevent)(struct device *dev, char **envp, int num_envp,
+                      char *buffer, int buffer_size);
+        void (*release)(struct device *dev);
+};
+
 /* interface for exporting device attributes */
 struct device_attribute {
         struct attribute        attr;
@@ -356,6 +363,7 @@ struct device {
 
         struct kobject kobj;
         char    bus_id[BUS_ID_SIZE];    /* position on parent bus */
+        struct device_type      *type;
         unsigned                is_registered:1;
         struct device_attribute uevent_attr;
         struct device_attribute *devt_attr;